The present invention relates to a rotary spray nozzle for spray guns, comprising a metallic outer housing and a plastic assembling element that are mounted together to form a rotary spray head wherein the metallic outer housing is equipped with a hollow chamber to accommodate and fix the plastic assembling element therein, economically simplifying the structure and the manufacturing process to reduce the cost of production and achieve standardized production thereby.
Please refer to FIG. 7. One conventional spray nozzle 10 utilized by spray guns is integrally molded via metallic material, whose manufacturing process (e.g. threaded and cut operations) can take a long time and boost the cost of production thereby. Thus, the conventional spray nozzle 10 can't achieve standardized mass production, which makes it quite uncompetitive on the market. Besides, the spray nozzle 10 is equipped with an annular groove 11 molded via lathing operation which features an inaccuracy and can easily come up with flawed products. And, a stop ring 20 can easily come off or inaccurately mount to the annular groove 11 thereof. In case the spray nozzle 10 is erroneously assembled onto a gun body 30, the spray gun can lose its function and its defective rate is easily increased.
To overcome the disadvantages of the aforementioned conventional spray nozzle 10, an improve spray nozzle is revealed in a Taiwan Patent No. 454574 and a U.S. Pat. No. 6,360,966 wherein plastic material is utilized and ejection-molded into a housing 40 (referring to FIG. 8) and an inner sleeve 50 that are further assembled into a spray head. Despite the saving of cost and time relative to the lathing operations involved in the above metallic spray nozzle, the housing 40 of said spray nozzle, however, has the interior equipped with a sleeve groove 41, a water-emitting slope 42, an oblique abutting surface 43, and a sliding section 44 therein so as to match to the stepwise design of the inner sleeve 50 thereby. Therefore, said spray nozzle features a complicated structure and fits only for the manufacturing of plastic material. In case the housing 40 is to be molded via, metallic material, the complex internal structure of the housing 40 will take a lot of time in an uneconomical manner. Thus, said improved spray nozzle is quite limited by the material applied thereof.